Mankind has made use of the power of water for thousands of years. The ancient Greeks used waterwheels to grind wheat into flour more than two-thousand years ago, and waterwheel technology spread across Europe during the height of the Roman empire. Over the subsequent millennia, hydropower technology spread to a variety of applications, including the production of electricity.
Hydroelectric power is generally known in the art, and hydropower is a common means of producing electricity around the world. In some South American countries, hydroelectric power accounts for more than 50% of the national supply of electricity. Most hydroelectric power is generated from the potential energy stored in water when that water is dammed and held, for example, in a reservoir. That potential energy is converted to kinetic energy when water is released from the reservoir through the dam, and the kinetic energy of the released water operates a turbine, which results in the production of electricity therefrom. A chief advantage of hydroelectric power is that, because hydroelectric facilities do not require an external fuel source, they are immune to variations in prices for fossil fuels such as oil, natural gas, or coal.
Despite the advantages of hydroelectric power, the hydroelectric facilities in existence today suffer from a number of drawbacks. With respect to the reservoir-and-dam method of producing electricity from hydropower, the amount of energy extracted from the water depends directly on the difference in height between the source of the water and the water outflow (this difference is referred to in the art as the head). Thus, such systems are not well-suited to use in areas having a substantially flat geography. Large hydroelectric facilities may also have undesirable environmental impacts. For example, dams along the pacific coast of North America have been shown to reduce the indigenous salmon population by preventing access to spawning grounds upstream. Engineers have attempted to address this issue by installing ‘fish ladders’ at many dams, but the results have shown only a limited success.
In addition to impacting fish populations, hydroelectric dams have an effect on downstream riverbeds. Because the water exiting the turbine generally contains little suspended sediment, the water tends to scour downstream riverbeds and erode riverbanks. Further, the change in flow rate over the daily cycle of a hydroelectric dam can lead to erosion of sandbars and other downstream structures. Dissolved oxygen content in the water released from the dam may be lower than normal, which can impact downstream flora and fauna, and temperature differences between the water held in the reservoir and the downstream water flow can also have a negative impact on biological populations downstream.
In addition to affecting plant and animal populations, hydroelectric dams may also adversely affect human populations in the area. Such projects may require the relocation of persons living in the area where the reservoirs are planned. In many places around the world, this can result in the loss of important cultural or ancestral lands. Further, in some such projects historically important sites have been lost.
The present invention provides a novel device for producing hydroelectric power that minimizes the disadvantages described above. These and other advantages of the present invention will become clear upon reading the description of the present device, below.